Termitomyces clypeatus produces cellobiose dehydrogenase (CDHtc) in cellulose medium with the highest yield (55.88 U mL(-1)) among all the reported fungal species. The enzyme has been isolated and purified from the culture filtrate. CDHtc was found to be a very thermolabile enzyme with the temperature optimum at 30 degrees C, while it exhibited a wide range of pH stability from pH 2.0 to 8.0. Lactose was efficiently converted to lactobionic acid in presence of the enzyme. Addition of glucose in the cellulose medium on the first day of growth induced a lag period in enzyme production but ultimately facilitated earlier CDHtc production and the yield was also comparable to that achieved in the cellulose medium. (C) 2008 Elsevier Ltd. All rights reserved.